After South Korea overturned its procurement agency's choice of the Boeing F-15SE Silent Eagle as its air force's next new fighter in September, and announced that it would buy the Lockheed Martin F-35A Joint Strike Fighter, Lockheed Martin and sources close to the company were not shy about predicting an Asian sweep for JSF. Japan had already chosen the new U.S. fighter over the Boeing F/A-18E/F Super Hornet and Eurofighter Typhoon (the latter was also passed over by South Korea), and Singapore was expected to follow suit imminently. Other nations in the region would do the same, it was argued, driven by the desire to match their neighbors and the growing threat from China.
The real picture may be more complex, according not only to competitors but analysts in Washington and elsewhere, and will be the outcome of many factors, including regional economic developments, the dynamics of the arms market and technological progress. South Korea and Japan's decisions were both influenced by changing national strategies as well as their close relationship to Washington, which has previously been known to exert heavy pressure on allies to acquire the JSF.
Japan acquired the F-35A—designed from the outset with an emphasis on strike into areas covered by advanced integrated air defense systems (IADS)—to replace F-4EJKai fighters used in the air defense role. This change in emphasis reflects changes in Japan's defense strategy (see page 64) under the conservative administration of Prime Minister Shinzo Abe. The new strategy views China as a rising adversary with long-term plans to acquire Japanese-held islands, emphasizes offensive weaponry and leans toward relaxing Japan's post-World War II constitutional ban on defense exports.
One sign of increasing tension between Japan and China is an increasing rate of quick-reaction launches by air-defense units. In the later Cold War years, Japan Air Self-Defense Force (JASDF) fighters were scrambled more than 800 times a year. From 1995 to 2005 the rate was usually under 200 per year but rose to 567 by 2012, F-35 program office leader Col. Koji Imaki told a conference in London in November.
JASDF's fighter force has been managed on a “three pillars” posture since the 1960s, Imaki said, with three types in service at any time. The force size has remained quite stable since the 1970s, declining to 12 from 14 squadrons, and is expected to comprise a mix of stealthy F-35s and upgraded conventional F-15s and Mitsubishi F-2s throughout the 2020s.
The current F-15J variant features an infrared search and track system, and the upgraded version—designated F-15MJ—will have the APG-63(V)1 radar (the most recent mechanically scanned variant) and a new electronic warfare suite. It will be armed with the new Mitsubishi AAM-5 short-range air-to-air missile, which externally resembles the German-Swedish IRIS-T—and the AAM-4B, an active-radar missile that has an active, electronically scanned array (AESA) antenna. (The earlier AAM-4 with mechanically scanned radar is already in service on some F-15s.)